Re: Perl Hash Files

This code reads values from STDIN and either creates or increments a hash appropriately. When you enter "Q" it will terminate and output the values...

use strict;
my %hash;
while(<STDIN>){
  chomp;
  last if $_ =~ /^q$/i; # quit if 'q' is entered
  if(exists $hash{$_}){ # exists, so increment
    $hash{$_}++;
  }
  else{                 # doesn't exist, so set to 1
    $hash{$_} = 1;
  }
}

my @array = sort keys %hash; # let's make the output sorted...
foreach(@array){
  print "$_ : $hash{$_}\n";
}
[download]

Is that what you meant?

map{$a=1-$_/10;map{$d=$a;$e=$b=$_/20-2;map{($d,$e)=(2*$d*$e+$a,$e**2
-$d**2+$b);$c=$d**2+$e**2>4?$d=8:_}1..50;print$c}0..59;print$/}0..20
[download]

Tom Melly, pm@tomandlu.co.uk

Comment on Re: Perl Hash Files Select or Download Code

Replies are listed 'Best First'.
Re^2: Perl Hash Files by jwkrahn (Abbot) on Dec 11, 2006 at 13:08 UTC
`if(exists $hash{$_}){ # exists, so increment $hash{$_}++; } else{ # doesn't exist, so set to 1 $hash{$_} = 1; }` [download] That can be more simply written as: `$hash{$_}++;` [download] But I think that the OP wants to increment the hash key instead of the value: `$_++ while exists $hash{$_}; $hash{$_}++;` [download]	[reply] [d/l] [select]